Excavator



July 7,- 1931. E. BAUER. 1,813,110

EXCAVATOR 2 Sheets-Sheet 1 Filed March 24, 1926 ilillll llIIll||llllllllllllllllllllllllll 1 0 I %)AM/w$0% Edvm1"d 155M911;

July 7, 1931.

E. BAUER EXCAVATOR Filed March 24, 1926 2 Sheets-Sheet 2 v Patented July 7,1931

. eration of the excavator.

UNITED STATES.

PATENT OFFICE EDWARD BAUER, OF MEWAUKEE, WISCONSIN, ASSIGNOR, BY MESNE ASSIGNMENTS, TO BUCYRUS-ERIE COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF DELAWARE EXGAVATOB Application filed March 24, 1926. Serial No. 97,009.

This invention relates to certain new and useful improvements in excavators and refers more particularly 'to a trip device for the dipper door.

While some types of excavators have been placed on the market as being capable of operation by one man, in actual practice it has been found necessary to provide an additional man to trip the dipper door, for due to a normal and necessary slack in the rope leading to the door trip, the operator must use both hands to quickly take up the slack and actuate the trip. As a result, the dipper oftentimes over-shoots the desired point of discharge and work is materially slowed.

Having'the above and -other objectionable features in mind, this ipvention contemplates as a primar object the provision of an improved mec a'nism whereby a minimum of effort is necessar to effect the tri ing of the dipper door so t at the services ofbut a single operator are required for the efficient op- Another object of this invention resides in the provision of an improved device which may be readily applied to any type of exca-. vator now in use or to excavators at the time p of their construction and which prevents the occurrence of slack in the dipper door trip operating rope so that the door trip may be.

instantly operated, a prime mover being utilized to efifect the operation of the trip.

A further object ofthis invention resides in the provision of an apparatus of the char acter described in which a motor is constantly rotated to maintain a tension on the' dipper 'vdoor trip cable and having means whereby an additional pull is applied to the cable by the motor to effect the tripping of the door.

- And a still further object of this invention,

resides in the provision of an improved device of the character described having an actuating member located within convenient reach of the operator and requiring but an instant engagement to effect the tripping of the dipper oor so that the operator need at no I -time relinquish control of the various levers for operating the excavator. v

With the above and other objects in view which, will appear as the description pro- 'changes in the ceeds, my invention resides in the novel constructlon, comblnatlon and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such hereindisclosed invention may be made as come within'the scope of the claims.

In the accompanying drawings, I have illustrated one complete example of the physical embodiment of my invention con-- recise embodiment of the I partly in elevation, illu'strating a slightly modified tion. p

The device constituting this invention is type of unit embodying my invendesigried for operating the door of an excavator dipper whether it be steam, gasoline,

electric or any other mechanically operated type and while the following description and accompanying drawings'illustrate the ap lication'of the invention to a shovel of the e ectric type, it is-to be understood that the use of the invention is not to be confined thereto.

Referring now more particularly tothe accompanying drawings, in which llke numer als designate like parts throughout the several views the numeral 5 'designates the turn table of an excavator on which an upper frame 6 is rotatably mounted,-the frame 6 ,carryin the o eratin mechanism and havg I; g

ing--;.a boom supported therefromand braced by cables 8 connected with the upper "end 9 of a truss frame 10 which braces the upper frame fiagainst the torque of the boom. As is customary, the excavating dipper 11 1s mounted on the outer end of a dipper handle 12 which is supported from the boom 7 I as at 13, for movement longitudinally and vertically about a horizontal pivot fixed with respect to the boom 7. As the specific shovel construction and operation forms no part of the present invention, further detail description thereof will be eliminated.

The dipper 11 has at its bottom closed by a door 14 which is hinged to the rear of the dipper, as at 15, so that the same nomally tends to open when the dipper boom or handle is out of vertical position. Slidably mounted on the door in brackets 16 is a locking bolt 17, the outer end 18 of which is engageable in a keeper 19 fixed to the dipper proper and adapted to be received within an aperture 20 in the outer free edge of the door. The locking bolt 17 is yieldably urged to locking position by a contractile spring 21 having one end connected with the dipper door and its other end connected with a lever 22 which passes through a slot 23 in the rear end of the locking bolt and is pivoted, as at 24, to the door. A chain,-cable or other operating member 25 has one end connected with the free end of the lever 22, as at 26, and its other end connected, as at 27, with a rotatable rod or drum 29 journaled, as at'30, in brackets carried by the dipper handle at i a point adjacent its outer 'end, the drum 29 being rotatable to wind the member 25 thereon through the medium of-a lever 31 having one end riveted or otherwise secured thereto, as at 32. i V.

The specific construction of the dipper door lock mechanism illustrated is of conventional design and the door 14 is closed by the manipulation of the dipper, as is customary in the operation of excavators, the bolt 17 swinging into the recess of the keeper 19 to lock the door closed. When it. is desired to dump the dipper, the operator causes the lever 31 to be moved rearwardly through the medium of an actuating cable 32 which has one end connected with the free end of the lever, as at 33,

so that the chain or other member 25 is wound about the drum 29 to disengage the bolt 17 from the keeper 19. As the tension on the cable 32 is released, the spring 21 unwinds the cable from the drum to permit the locking of the door after it closes.

w As the dipper handle 12 is extended and retracted throughout substantially its entire len h during the operation of the excavator, it is essential that sufiicient slack be provided in the cable 32 to accommodate the maximum,

extension of the'dipper'and when the dipper is to be dumped when in retracted position, 1t is necessary that the slack in the cable be first taken up before movement can be im-' parted to the lever 31,'as previously described. This resnltsin considerable loss of time and in order toefiiciently operate the excavator it is necessary to provide an additional operator whose duty it is to trip the dipper door, thus materially increasing the over-head expense incidental to the operation of the excavator.

Attempts have been made in the past to overcome these objectionable features such as exemplified in Letters Patent No. 1,435,- 109, issued David De Santo, November 7, 1922. Asit is highly essential that the dipper door be tripped with a minimum of effort, if the excavator is to be entirely worked by a single operator, the, device illustrated in the accompanying drawings provides a single control button, cord, or other actuating member which is located at a convenient place to the operator so designed that all that is re- .quired for the tripping of the door is but a with flanges 41 and 42 adapted to be friction ally engaged with the adjacent surfaces of the plates 38 and 39, respectively, which are lined with a friction lining of suitable material 43. The friction plate 38 is keyed or otherwise splined to the shaft 36, as at 44, and the clutch plate 39 is normally free thereon, being yieldably held free of the drum member by an expansile spring 45 mounted on the shaft 37 between the clutch plate and drum, said spring extending into a recess 46 in the adjacent end of the drum and pressing against one side of a bearing 47 for the drum.

Adjustable on the shaft 37 adjacent the clutch plate is a collar 48 which, is provided with a plurality of radially extended pairs of cars or lugs 49 between'which dogs or levers 50 are medially pivoted,the inner ends 51 of the levers being engageable with the outer inclined surface of the clutch plate and the outer ends 52 thereof being rounded and engageable with a cone collar 53 which is slidable on the drive shaft. The cone collar 53 has its outer portion annularly grooved, as

v at 54, to receive bearing blocks 55 pivotally connected, as at 56, with the ends of a yoke or U-shaped member 57 of an operating lever 58 which is medially pivoted, as at 59; from an extension 60 secured to the adjacent standcord 68 fixed thereto which extends to a posi-- tion located conveniently to the operator.

- The-prime mover 64 constantly operates ,tension on the drum bearing 47 to urge the flange 41 of the drum intofrictional engagement with the friction plate 38 so that the cable 32 tends to wind on the drum, to which result the friction between the plate 39 and the'drum (through the spring 45) also con tributes to some extent.

The tension pro.-

duced in the cable 32 by this total friction,

however, is not enough to extend the spring 21 sufliciently to permit tripping the latch.,

.The spring '45 in addition to maintaining this frictional contact, normally maintains the clutch plate free of the drum. flange 42 and when it is desired to trip the dipper door, a slight pull is given the member 68 which moves thelever 58 on its pivot 59, forcing the, cone 53 between the ends 52 of the levers 50 and moving the clutch plate 39 to engage its frictional surface 43 with the flange surface 42 to lock the drum to the shaft 37 and wind the cable'32 thereon. As the r a cable 32 winds on the drum, the lever 31 rotates' drum 29 winding the cable or chain 25 thereon to disengage the locking bolt 17 from the dipper keeper .19.

As will be readily evident, when the parts are in the positions illustrated in Eigure 3, there is a normal sli between the drum and the friction plates w ich is suflicient to maintain the cable 32 taut without; overcoming the spring 21, but when the clutch plate 39 is moved to direct engagement with the drum,- the drum is locked between the friction and clutch plates and turns with the shaft. "There being no slack in the cable 32, the di per door is instantly opened thus requiring but a momentary contact on the part of the operators hand with the actuating member 68.' 'After the operator has released the actuating member 68 the spring 45 instantly expands to disengage the clutch plate from the drum and the spring 21 being greater than the frictional contact between the drum and the friction platesunwinds the cable or chain 25 from the drum 29 returning the locking bolt 17 to its locked position. y

In Figure 4, a slightly modified construction of my invention is illustrated wherein the lever 58 is operated by a solenoid -70 mounted on a bracket 71 secured to one of the standards 35 and havin a tubular core 72 in which an armature 3 is slidable'. The outer end of the armature is ivotally connected, as at 74, with the outer ree end of the.

lever 58 and the mass of the armature is normally positioned below the magnetic center of the solenoid so-that ener 'zation of the .'-'solenoid draws the armature intothe core 72 switch 76 is located on one of the control handles 77 within convenient reach of the operators hand! To dump the dipper, button 7 6 is pressed to complete the contlnuity of the solenoid circuit, energizing the solenoid and attractin the armature thereinto.

While have illustrated an electrical motor as the'means for actuating my improved device, it will be appreciated that any other appliance may be utilized such as a connection with the prime mover of the excavator proper, a turbine or any other means. The device being a unitary structure, as illustrated in Figure 3, may be readily applied to any style of excavator without requiring modification of its construction and thus may be sold as a unit entirely apart from the excavator, :p

What I claim as my invention is;

1. In an excavator having a dipper rovided with a discharge door, a locking olt for securing the door closed and a trip cable connected with the locking bolt whereby a pull on the cable greater than a certain amount permits the openin ofthe dipper door, a drive shaft, means or continuously rotating the drive shaft, a drum rotatably mounted on the drive shaft and about which the, trip cable is adapted to be wound, a friction member fixed to the drive shaft, means providing a slipping frictional contact between the friction member and drum, whereby the drumnormally tends to wind thetrip cable thereon to'*ma1ntain .a tension on the cable sufiicient to take up all slack therein .but insufiicient to actuate the locking bolt,

and means for increasing the frictional contact between the friction member and the? drum .to increase the tension on the trip cable 221a point suflicient to actuate the locking t. r i

2. In an excavator having a dipper pro-, vided with a discharge door, a locking bolt for securing the door closed and a trip cable-- providing a'slipping frictional contact between the friction member and the drum whereby the drum normally tendsto wind the trip cable thereon to maintain a tension thereon suflicient to take up all slack there in but insuflicient to actuate thelocking bolt, and clutch means operable to drivingly connect the drum member with the shaft where.- i

to the drive shaft and engageable with one end of the drum, means providing a yielding engagement between the drum-member and the friction plate whereby the drum tends to rotate with the shaft to maintain the trip cable taut without actuating the locking bolt, and a clutch plate engageable with the other end of the drum to increase the drive connection between the drum and shaft to an extent sufiicient to withdraw the locking bolt.

4. In an excavator having a dipper provided with a dischargedoor, a spring pressed locking bolt for securing the door closed and a trip cable connected with the locking bolt whereby a pull on the cable greater than a certain amount permits the opening of the dipper door, a drive shaft, means for continuously rotating the drive shaft, a drum rotatably mounted on the drive shaft and about which the trip cable is wound, a plate fixed to the drive shaft and engageable with one end of the drum, means providing a slipping frictional engagement between the drum member and the friction plate whereby the drum tends to rotate with the shaft 4 to maintain the trip cable taut without ac- 'tuating the spring pressed locking bolt, a

clutch plate engageable with the other end of the drum to increase the drive connection between the drum and shaft to an extent sufficient to withdraw the locking bolt, an actuating lever for the clutch, and an operating cable connected with one end of the lever and extended to a location convenient to the excavator operatorJvhereby a slight pull I vided with a discharge door, a. locking bolt for securing the door closed and a trip cable connected with the locking bolt wherebya pull on the cable greater than a certam amount permits the opening of the dipper door, a drive shaft, means for continuously rotating the drive shaft, a drum rotatably mounted on the drive shaft and about which the cable is wound, a friction plate fixed to the drive shaft and engageable with one end of the drum, means providing a slipping frictional engagement between the drum member and the friction plate whereby the drum tends to rotate with the shaft to maintain I the trip cable taut without actuating the locking bolt, a clutch plate engageable with thetother end of the drum to increase the drive connection between the drum and shaft to an extent sufficient to withdraw the looking bolt, an actuating lever for the clutch, a solenoid, an armature connected with the lever and arranged within the sphere of influence of the solenoid, an electric circuit including said solenoid, and a circuit making and breaking device for operating the circuit and located in a position convenient to the excavator operator.

6. In an excavator having a dipper provided with a discharge door, a locking bolt for securing the door closed and a trip cable connected with the locking bolt whereby a pull on the cable greater than a certainamount permits the opening of the dipper door, a drive shaft, means for continuously rotating the drive shaft, a drum'rotatably mounted on the drive shaft and about which the trip cable is wound, a friction plate fixed to the drive shaft and engageable with one end of the drum, means prov ding a yieldin engagement between the drum member an the friction plate whereby the drum tends to rotate with the shaft to maintain the trip cable taut without actuating the locking bolt, and a clutch plate engageable with the other end of the drum to increase the drive connection between the drum and shaft to an extent suflicient to withdraw the locking bolt, the means last above mentioned serving normally to'hold the clutch plate out of the operative engagement with the drum. (k

y an excavator having a di per provided with a discharge door, a loc 'ng bolt for securing the door closed and a trip cable connected with the locking bolt whereby a pull on the cable greater than a certain amount rmits the opening of the dipper door, a rive shaft, means for continuously rotating the drive shaft, a drum rotatably mounted on the drive shaft and about which the trip cable is wound, a friction plate fixed to the drive shaft and engageable with. one end of the drum, spring means providing a yielding engagement between the drum member and the friction plate whereby the drum tends to rotate with the shaft to maintain the trip cable taut without actuating the locking bolt, and a clutch plate engageable with the other end of the drum to increase the drive connection between the drum and shaft to an the clutch l t out of operative engagement. i2 6 J with the drum.

8. .In a trip for power shovels, thecom{ bination of: a tripmcable; twov constantly ro- 1 tating power dis a "drum'forsaid trip cable located between-said. two disks; single means normally tending to, hold one of said" disks in frictional contact with the drum and the other disengaged therefrom; and means for clamping the drum between the two disks. 9. In a trip for power shovels, the combination of: a tri' cable; two constantly rotating power dis s; a drum for said trip cable; single means normally tending to hold one of said disks in frictional contact with the drum and the other disengaged therefrom; and means for engaging the drum and the normally disengaged disk. 10. In a trip for power shovels, the combination of: a trip cable; two constantly rotating power disks; a drum for said trip [5 cable; single means normally tending to hold one of said disks in frictional contact with the drum and the other disengaged therefrom; and means for engaging the drum and the normally disengaged disk, and at the same time increasing the pressure between the drum and the normally contacting disk. 11. In a semi-automatic trip for power shovels, a trip cable, a drum therefor, power means, manually actuated means for connecingthe power means with the drum, a friction member normally pressing against the drum, said friction member being connected with the power means so as to be rotated thereby, a spring for causing said friction member 7 to engage the drum continually, means for adjusting the tension of said spring whereby a proper frictionmay be secured for caus in the drum to take up any slack in said ca le without however imparting sufficient tension to said cable to cause it to function for tripping purposes.

- 12. In a power dipper door latch releasing device, a rotatably mounted shaft, a pair of friction disks carried by said shaft, one of 40 which disks is movable toward and away from the other, a druinmounted for independent rotary movement between said disks,

a cable secured to and adapted to wind upon said frame, which cable is connected to the dipper door latch of the shovel with which the device is associated, manually operable means for causing the disks to frictionally engage thecable carrying drum with suflicient force to actuate the cable for tripping,

and yieldin pressure means associated with said manna y operable means for producing suiflcient frictional connection between the Shaft and the drum to cause said drum to rotate and take up the slack in the cable that is carried thereby. r

' In testimony whereof I aflix m signature.

EDWARD AUER. 

